1. Field of the Invention
The present invention relates to a face recognition apparatus and method for recognizing a face to identify a person, to read an expression on the person's face, or to determine the condition of the person, and in particular, to a face recognition apparatus and method which improves the accuracy in recognizing the person by obtaining a full face image.
2. Description of the Related Art
As information technologies advance, man-machine interfaces, which users can easily operate, are increasingly in demand. Accordingly, the technology for identifying and verifying a user in the man-machine interface has become of increasing importance. There are various identification methods, e.g., a method using a storage medium which belongs only to the person (e.g., a magnetic card or an IC card), a method using matching of information which only he knows (e.g., a password), and a method using the features of the person's body. One of the methods using the features of the human body which identifies the person based on a digital image of his face has been developed.
This method is not limited to identification, but can recognize the expression of the user to determine the user's feelings. Thus, the technique for recognizing a human face has become important. For example, the method may be used to determine happiness, anger, and weariness, or to determine whether the person is an adult or a child.
In the method for recognizing a human face using digital image analysis, it is more difficult to identify the face, to detect its elements, and to extract the features of the face image as seen from the side, or obliquely from a high, low, right, or left angle, than as seen from directly in front of the full face. When receiving the image of the head just from behind or obliquely from behind, the image is of the back of the head, and the face cannot be recognized.
To improve the accuracy of recognition in the face recognition device of conventional techniques, the person needs to be directly in front of the image pick-up device. However, to improve the facility for users and compatibility with the machines so as to expand the application of the technique, it is not expedient that the person must take such an action.